There have been numerous attempts to provide compact power units for attachment to a golf bag cart and a number of these have proven to be satisfactory to some extent. On the other hand, some of them have had shortcomings which included the inability to easily turn and maneuver the golf cart, particularly on cramped to close quarters. Examples of one type of these prior art devices are shown in the U.S. Pat. Nos. 2,903,082, issued Sept. 8, 1959; U.S. Pat. No. 3,094,185 issued June 18, 1963; 3,561,555 issued Feb. 9, 1971; and 3,815,699 issued June 11, 1974. These attachments combined the drive wheels, battery and motor onto one frame, which frame was then attached rigidly to the frame of the golf cart.
Other examples of prior art devices of this generaly character are shown in the U.S. Pat. Nos. 3,199,621 issued Aug. 10, 1965; and 3,330,371 issued July 11, 1967. The devices shown in these two patents had the driven wheels and the power units therefor mounted on one frame, which frame was then swivelly or swingably mounted to the frame of the golf bag cart.